Apparatus and method for coding a time-discrete audio signal to obtain coded audio data and for decoding coded audio data

US7275036B2 · kind B2 · utility

Assignee

• Fraunhofer-Gesellschaft zur förderung der angewandten Forschung e.V. · DE

Inventors

• Ralf Geiger · Erlangen, DE
• Thomas Sporer · Ergolding, DE
• Karlheinz Brandenburg · Erlangen, DE
• Juergen Herre · Erlangen, DE
• Juergen Koller · Erlangen, DE
• Joachim Deguara · Felton, US

Key dates

• Filing date: Oct 15, 2004
• Grant date: Sep 25, 2007
• Expiry date: Jun 15, 2025

Classification

• Technology area (CPC G): Physics
• CPC primary: G10L2019/0005
• WIPO field: Computer technology
• WIPO sector: Electrical engineering

Abstract

A time-discrete audio signal is processed to provide a quantization block with quantized spectral values. Furthermore, an integer spectral representation is generated from the time-discrete audio signal using an integer transform algorithm. The quantization block having been generated using a psychoacoustic model is inversely quantized and rounded to then form a difference between the integer spectral values and the inversely quantized rounded spectral values. The quantization block alone provides a lossy psychoacoustically coded/decoded audio signal after the decoding, whereas the quantization block, together with the combination block, provides a lossless or almost lossless coded and again decoded audio signal in the decoding. By generating the differential signal in the frequency domain, a simpler coder/decoder structure results.